The Capabilities and Limitations of Flow Simulation

One of the grey areas of Simulation swirl around the SolidWorks Flow Simulation product-line, where the capabilities and limitations are critical to ensure successful implementation. Earlier this week, we had a potential customer inquire into the functional capabilities of Flow Simulation.

Flow Simulation is an excellent mid-range fluid flow product if you are trying to simulate anything from liquids to gas flow. It can be utilized in a wide range of applications from electronics to valves to HVAC to medical and automotive/aerospace applications, and also where fluid flow coupled with thermal analysis is a requirement.

Below is a compiled list of the capabilities and limitations of the SOLIDWORKS Flow Simulation productline as of 2009:

One component or up to ten independent species -liquid-liquid mixing, or gas-gas mixing

Forced, free or mixed convection – heat transfer

Conjugated heat transfer (fluid, solid), conduction and convection

Porous Media

Radiation

Steady state and Transient (time-dependent) fluid flow

Rotating Frames of Reference

TEC coolers/heat sink emulators/Thermostats

Cavitation

Relative Humidity

What Flow Simulation cannot do

Phase Change – The Flow package cannot handle materials cooling and transforming from gas-to-liquid, or molten liquid-to-solid. Similarly, it cannot handle materials heating from molten solid-to-liquid, or liquid-to-gas. This requires special high-end non-linear and complex formulations specifically for modeling entropy and chemical/molecular changes to account for cool down etc. Eg: plastic flow throw an injection mold as it cools and solidifies.

Co-existence of different phases – Flow Simulation cannot simulate a liquid and a gas in the same cavity. For instance, water flowing out of a nozzle into air (since water and air exist in the same cavity after the water flows out). Similarly, sprays (where fluid bubbles are sprayed into air). Different fluids (liquids/gases) can co-exist in a Flow Simulation if they exist in different cavities or volumes.

Free Surface Phenomena – Flow Simulation cannot simulate the top layer of a liquid sitting in an open tank. This again requires highly non-linear and complex formulae that are characteristic of high-end packages.

Particles/Suspensions – Flow Simulation cannot simulate solid/liquid suspensions in a fluid where the suspensions can influence the pattern/parameters of flow. Since Flow Simulation cannot have two different phases in the same volume, it does not support solid particles in a fluid stream/liquid particles in a fluid stream/gas trapped in a liquid stream etc.